Recloseable container



May 23, 1967 5. J. RIVMAN ETAL RECLOSEABLE CONTAINER Filed Sept. 7, 1965IN v: N m R s dkMz/sz J lea MAN HEMP) A. themaler United States PatentOffice 3,321,126 Patented May 23, 1967 3,321,126 RECLOSEABLE CONTAINERSamuel J. Rivmau, White Plains, N.Y., and Henry Alan Carysforth,Wyckolr, N.J., assignors to Gulf Oil Corporation, Pittsburgh, Pa., acorporation of Pennsylvania Filed Sept. 7, 1965, Ser. No. 485,262Claims. (Cl. 229-65) The present invention relates to plastic containersand methods for making such containers; more particularly, thisinvention relates to closable plastic containers which are easily openedand easily sealed shut again, and to methods for making such containers.

Plastic bags, particularly bags made of polyethylene, have come intogreat popularity for packaging various materials and articles. Forexample, clothing or similar articles often are packed in heat-sealedpolyethylene bags. Often a prospective purchaser desires to open the bagto inspect its contents. Because the bag is heat-sealed, it must be cutor torn open to permit this inspection. If the customer decides not tobuy the article, it will be difiicult to sell because its protective baghas been destroyed. This is true even if the torn bag is laboriouslysealed shut again by conventional methods.

Often, several perishable articles such as fruits and vegetables arepacked in one plastic bag. As pointed out above, once the bag is torn orcut open, it cannot be rcclosed easily. Therefore, any articlesremaining in the bag after it is opened are unprotected fromcontamination and easily could fall out. If it were possible to easilyopen the bag without cutting or tearing it, and if it were easilyresealable, it would be convenient for the user to take a few items outof the bag, and then reseal the bag, thus maintaining the protection ofthe remaining items.

Accordingly, one object of the present invention is to provide a plasticbag which is easily opened and rescaled without the use of adhesivetape, heat-sealing, or other means requiring special equipment.

It is a further object of the present invention to provide a simple,sturdy, long-lasting reclosable plastic bag which is relativelyinexpensive to manufacture.

In the past, bags made of paper and similar materials have been providedwhich have a metallic strip across the top which can be bent over at itsends for resealing the bag after it has been opened. However,considerable problems have been met in securing such metal strips to thebag material. Additionally, often it has been required that the stripshave considerable lateral extent so as to be easily handled by the user.This increases the amount of metal required for the strips and makesthem unduly expensive.

Accordingly, another object of the present invention is to provide arelatively inexpensive, reliable and troublefree method of securing ametal closure member to a plastic container, and to provide a metalresealing member of substantial lateral extent with a minimum amount ofmetal.

A further object of the present invention is to provide a uniquecontainer structure which is foldable to cover and protect objects to becontained in the structure.

The drawings and description that follow describe the invention andindicate some of the ways in which it can be used. In addition, some ofthe advantages provided by the invention will be pointed out.

In the drawings:

FIGURE 1 is a perspective, partially broken-away view of a plastic bagof the present invention;

FIGURE 2 is an enlarged cross-sectional, partially broken-away viewtaken along line 2-2 of FIGURE 1;

FIGURE 3 is an enlarged perspective view of the bag shown in FIGURE 1with the bag flap folded over during an intermediate step in the processof closing the bag;

FIGURE 4 is a perspective view of the bag of FIG- URE 1 filled withobjects to be stored in it and sealed in accordance with the presentinvention;

FIGURE 5 is a perspective and partially schematic view of apparatus usedin the process of manufacturing containers in accordance with thepresent invention;

FIGURE 6 is a perspective, partially broken-away view of anotherembodiment of the container of the present invention;

FIGURE 7 is a view similar to FIGURE '6 of the container shown in FIGURE6 with the bag as originally sealed but partially opened; and

FIGURE 8 is a perspective view of another embodiment of the containerstructure of the present invention.

A polyethylene plastic bag 10 is shown in FIGURE 1 of the drawings. Thebag 10 is formed from a sheet 12 of thin polyethylene film which isfolded upon itself along a bottom fold line 14. The folded-togethersides of the sheet 12 are heat-sealed together at edges 16 and 18. Oneedge 19 of the sheet 12 forms one edge of the opening of the bag, and aportion 20 of the opposed side-wall of the bag 10 extends above the edge19 to form a flap.

In accordance with the present invention, a relatively thin corrugatedwire 22 is secured to the rear surface of flap 20 by means of a strip 24of plastic material such as polyethylene. Wire 22 extends across flap 20and serves as a closure member. The corrugated wire 22 is made ofrelatively malleable and inexpensive metal.

The process of closing the bag 10 is quite simple. The bag is filledwith the contents to be stored, the flap 20 is folded forwardly over theedge 19 to the position shown in FIGURE 3, is folded once more in thesame direction, and then the ends of the corrugated wire 22 are foldedover in the manner shown in FIGURE 4 so as to secure the bag shut.

Opening and re-closing the bag similarly is simple. First, the ends ofthe wire closure element 22 are unbent, the flap 20 is unfolded and thecontents are removed. The bag is re-closed in substantially the same wayas it originally was closed.

There are many advantages in the use of the corrugated wire 22 as thebag closure member. The corrugations in the wire and the relatively wideencapsulating plastic strip 24 supporting it make the wire easy to graspand bend, in much the same manner as a wide, solid metal strip, butwithout the relatively large amount of expensive metal which is used inthe metal strip. Furthermore, since the wire is tightly encapsulated andprotected by the plastic securing it to the flap 20, it need not be madeof expensive corrosion-resistant metal. Additionally, the use of wire asa closure member is uniquely adapted to automatic mass-productionmethods such as those described below.

The plastic bag shown in FIGURE 1 is manufactured by the novelmass-production method illustrated in FIG- URE 5. A sheet 12 ofpolyethylene film is supplied from a roll. First the film is foldedalong line 14 and then is fed over a series of drive and idler rollers28 Wtih the rear surface of flap 20 facing upwardly.

The folded sheet 12 first passes beneath a spool 30 on which a roll ofwire 32 is stored. The spool 30 is rotatably mounted on a support shaft34. The wire 32 is unwound from the spool 30 and is fed through acorrugating device 38 which comprises a pair of loosely meshed spurgears between which the wire passes so that the wire takes the shape ofthe gear teeth. The corrugated wire 22 emerging from the corrugatingdevice 38 is laid upon the back surface of flap portion 20 of the sheet12.

The sheet 12 then passes beneath an extruding machine 40 which extrudesa thin strip 24 of heated thermoplastic material such as polyethyleneonto the back surface of flap 20 over the corrugated wire 22, thusheat-sealing the strip 24 to the flap 20 and simultaneouslyencapsulating the corrugated wire 22 and fastening it securely to the Aheated knife 44 and a cold knife 46 are periodically brought downtogether to form the plastic sheet 12 into bags. The heated knife 44simultaneously cuts the sheet into bag-widths and seals the edges 16 and18 together. The knife 46, which is air-pressure-actuated, cuts thematerial of the flap along the same line as the cut made by the hotknife 44, and simultaneously cuts the wire 22.

The above method of attaching the wire closure member to the sheet 12has many advantages. It is relatively simple, inexpensive and is ideallyadapted to be performed by automated equipment. Furthermore, with theuse of corrugated wire 22 instead of solid metal strip for the closuremember, the length of the closure member contracts with the length ofthe plastic strip 24 as both strip 24 and wire 22 are cooling, thuspreventing the ends of the wire from extruding out from the sides of thebags and possibly injuring the users of the bag or snagging on the usersclothing. This extreme contraction is made possible by the corrugatedshape of the wire and is not obtained from solid metal strips.

Referring now to FIGURES 6 and 7, the bag 48 shown in these figures issubstantially the same as bag shown in FIGURES 1 through 4 except thattwo corrugated wires 50 and 52 are secured to the flap 20 by means ofthe strip 24. Also, during the bag manufacturing process, the flap 20 isfolded down over the edge 19 and the flap 20 is heat-sealed to the frontwall 12 of the bag 48 along line 54. Typically, the bottom of this bagis left open and the bag is filled through the open bottom during thismanufacturing process. Then the bottom is sealed and the filled bag isshipped to the customer.

In accordance with a further aspect of the present invention, when thecustomer Wishes to open the bag 48, he may grasp the lowermostcorrugated wire 50 and pull outwardly as is illustrated in FIGURE 7,thus tearing through the strip 24 and allowing the customer to open thebag along the line where wire 50 has been pulled loose. Then, when thecustomer wishes to reclose the bag, the second corrugated Wire 52 may beused to reclose the bag 10 shown in FIGURES 1 through 4. Thus, the novelcorrugated wire member of the present invention is used for a doublepurpose; both to make an easilyopened bag, and to make the bag easilyre-closa-ble after it has been opened.

Referring now to FIGURE 8, there is shown another container structure 56which is an embodiment of the present invention. Structure 56 may beused, for example, to wrap objects 58 such as boxes of vegetables or thelike before freezing them. Thus, the present invention is used to form aconvenient plastic wrapper which can be applied without specialheat-sealing tools or the like. The corrugated wire 22 and the strip 24are applied in the manner described above in connection with FIG- URE 5.If it is desired to wrap rectangular objects, the strip is convenientlyplaced nearer one edge of the plastic sheet 12 than the other edge sothat the other edge may be folded over on the top of the object 58 andthe wrapper will properly cover the object. Then, the ends of wire 22and strip 24 are folded up and over the top of the object 58 to hold theplastic wrapper 56 in place. No adhesive tape or special sealingcompounds are required to seal the package shut.

While only two-wall bags have been shown in the illustrated embodiments,it is to be understood that sidewalls may be added to the bag structureswithout departing from the teachings of the present invention. Inaddition,

it should be understood that various different flexible plasticmaterials can be used in containers made in accordance with the presentinvention, including cellophane, paper and other traditional plasticmaterials, as well as polyethylene and other modern materials. Further,wire closure elements other than corrugated wire can be used. Forexample, plastic-coated wire-ties, such as are used for fasteningvegetable stems together, etc., may be used either by encapsulation andheat sealing as described above, or by heat sealing alone byconventional heatsealing procedures. Various other changes ormodifications in the embodiments described may occur to those skilled inthe art and these can be made without departing from the spirit or scopeof the invention as set forth in the claims.

We claim:

1. An easily-reclosable container made of flexible plastic material,said container including a pair of opposed side walls, said side Wallsforming at one pair of edges an opening for said container, one of saidedges of one of said side walls extending outwardly from said containerto form a flap at said opening, a plastic-encapsulated wire secured tosaid flap and extending transversely across said container at saidopening, the plastic encapsulating said wire forming alaterally-extending support platform for said wire, said supportplatform supporting said wire against rotation.

2. A structure foldable for forming a flexible plastic container, saidstructure comprising a closure strip including a length of corrugatedwire encapsulated in a flexible plastic material, said material formingrelatively stiff lateral extensions for supporting said wire, and asheet of flexible plastic filrn, said closure strip being secured tosaid film in a position adapted to form said film into a closedcontainer.

3. A container as in claim 1 in which said wire is corrugated.

4. A container as in claim 1 including another wire encapsulatedsubstantially parallel to but spaced from said wire, said flap beingadapted to be folded over to close said opening by being secured to oneof said side walls, said other wire being adapted to be pulled away fromsaid container to tear said flap and open said container.

5. An easily-reclosable container made of flexible plastic material,said container including a pair of opposed side walls, said side wallsbeing joined together at their edges to form a polyethylene bag with anopening with an edge of each of said side wall adjacent said opening,one of said edges of one of said side walls extending outwardly fromsaid container to form a flap at said opening, a plastic-encapsulatedcorrugated wire secured to said flap and extending transversely acrosssaid container at said opening, the plastic encapsulating said wireforming a laterally-extending support platform for said wire.

References Cited by the Examiner UNITED STATES PATENTS 2,973,131 2/1961Mead et a1. 22966 3,024,962 3/1962 Meister 22962 3,159,096 12/1964Tocker.

FOREIGN PATENTS 974,419 9/1950 France. 815,321 10/1951 Germany. 205,1898/1939 Switzerland.

JOSEPH R. LECLAIR, Primary Examiner.

D. M. BOCKENEK, Assistant Examiner.

5. AN EASILY-RECLOSABLE CONTAINER MADE OF FLEXIBLE PLASTIC MATERIAL, SAID CONTAINER INCLUDING A PAIR OF OPPOSED SIDE WALLS, SAID SIDE WALLS BEING JOINED TOGETHER AT THEIR EDGES TO FORM A POLYETHYLENE BAG WITH AN OPENING WITH AN EDGE OF EACH OF SAID SIDE WALL ADJACENT SAID OPENING, ONE OF SAID EDGES OF ONE OF SAID SIDE WALLS EXTENDING OUTWARDLY FROM SAID CONTAINER TO FORM A FLAP AT SAID OPENING, A PLASTIC-ENCAPSULATED CORRUGATED WIRE SECURED TO SAID FLAP AND EXTENDING TRANSVERSELY ACROSS SAID CONTAINER AT SAID OPENING, THE PLASTIC ENCAPSULATING SAID WIRE FORMING A LATERALLY-EXTENDING SUPPORTING PLATFORM FOR SAID WIRE. 